Influence of Emulsifiers and Nonfat Milk Solids on Physical Stability of Reconstituted Lyophilized Milk Products

The purpose of this study was to evaluate the effects of emulsifier concentration and I-ILB number on the physical stability of reconstituted lyophilized milk products which contained different concentrations of NFMS. Model milk product systems containing 6% milk fat, 8% sucrose, and 0-10% NFMS were prepared. Each of the systems contained an emulsifier. These were characterized by an tILB number of 8, 11, or 14. The emulsifiers were used at concentrations of 0.00, 0.24, or 0.48%. The mixtures were homogenized and ]yophilized, then reconstituted to their original composition. The fat and total solids content was determined before lyophilization, and on the reconstituted liquid after lyophilization. The amount of milk fat recovered in the reconstituted products increased at the higher levels of NFMS (P<0.01). The stability o the milk fat emulsion also increased with increased concentrations of emulsifier (P< 0.05) and optimum emulsifier ~ILB numbers were between 11 and 14.